Added HeaderTransformer strategy interface and HeaderTransformingMessageHandler adapter (INT-307).

org.springframework.integration/src/test/java/org/springframework/integration/transformer/HeaderTransformingMessageHandlerTests.java

@@ -0,0 +1,74 @@
+/*
+ * Copyright 2002-2008 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.integration.transformer;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNull;
+
+import java.util.Map;
+
+import org.junit.Test;
+
+import org.springframework.integration.message.Message;
+import org.springframework.integration.message.MessageBuilder;
+
+/**
+ * @author Mark Fisher
+ */
+public class HeaderTransformingMessageHandlerTests {
+
+	@Test
+	public void addHeader() {
+		HeaderTransformer transformer = new HeaderTransformer() {
+			public void transform(Map<String, Object> headers) {
+				headers.put("header2", "baz");
+			}
+		};
+		HeaderTransformingMessageHandler handler = new HeaderTransformingMessageHandler(transformer);
+		Message<String> message = MessageBuilder.fromPayload("foo").setHeader("header1", "bar").build();
+		Message<?> result = handler.handle(message);
+		assertEquals("bar", result.getHeaders().get("header1"));
+		assertEquals("baz", result.getHeaders().get("header2"));
+	}
+
+	@Test
+	public void replaceHeader() {
+		HeaderTransformer transformer = new HeaderTransformer() {
+			public void transform(Map<String, Object> headers) {
+				headers.put("header1", "baz");
+			}
+		};
+		HeaderTransformingMessageHandler handler = new HeaderTransformingMessageHandler(transformer);
+		Message<String> message = MessageBuilder.fromPayload("foo").setHeader("header1", "bar").build();
+		Message<?> result = handler.handle(message);
+		assertEquals("baz", result.getHeaders().get("header1"));
+	}
+
+	@Test
+	public void removeHeader() {
+		HeaderTransformer transformer = new HeaderTransformer() {
+			public void transform(Map<String, Object> headers) {
+				headers.remove("header1");
+			}
+		};
+		HeaderTransformingMessageHandler handler = new HeaderTransformingMessageHandler(transformer);
+		Message<String> message = MessageBuilder.fromPayload("foo").setHeader("header1", "bar").build();
+		Message<?> result = handler.handle(message);
+		assertNull(result.getHeaders().get("header1"));
+	}
+
+}